


One Night of Many

by minbins



Category: Monsta X (Band), SEVENTEEN (Band)
Genre: Alternate Universe - Non-Famous, Blowjobs, Established Relationship, Explicit Sexual Content, Gym Owner Mingyu, Kihyun is 35, Love, M/M, Mingyu Likes To Feel Small, Mingyu is 28, Professor Kihyun, Setting: A Night at Home, Slice of Life, handjobs
Language: English
Status: Completed
Published: 2021-02-04
Updated: 2021-02-04
Packaged: 2021-03-15 11:54:38
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,070
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29188878
Author URL: https://archiveofourown.org/users/minbins/pseuds/minbins
Summary: Mingyu claws at Kihyun’s perfect thighs, and thinks about love.
Relationships: Kim Mingyu/Yoo Kihyun
Comments: 2
Kudos: 49





	One Night of Many

“Hyung,” Mingyu whines, butting his head against Kihyun’s leg. He’s sat on the floor in front of his boyfriend, Kihyun’s slim fingers absentmindedly petting his hair as they (read: _Kihyun)_ watch a documentary. It’s nice and all, sure, but Mingyu should not be forced to sit still after form-filing day at work. It’s unethical, in his humble opinion. “This is _boring._ Can’t we do something fun?”

“This _is_ fun, darling,” Kihyun replies, in that disinterested sort of tone that means _be quiet, Mingyu._ Mingyu doesn't intend on heeding the warning. “I told you I was planning on watching this tonight, and you still came over. That’s on you.”

“I didn’t realise it was going to be _three hours long,”_ Mingyu counters. “Why does a documentary on old dusty bones have to be three hours long, hyung? Why?”

“This documentary is about the historical impact of _carbon dating,_ darling.” Kihyun pulls his hair, just enough to hurt. Mingyu’s traitorous cock twitches in his sweats. _“Not_ ‘dusty old bones’ — if you’d only pay attention, you would know that.”

Kihyun is a professor at a respectable, highly-ranked university. Mingyu owns a gym nearby, specialising in personal training. They seem an unlikely couple, as such. 

Still, from the moment a disgruntled looking Kihyun had trailed into his gym with the opening words _‘My friends bullied me into coming here’,_ Mingyu had been smitten. It had taken a full _three months_ for Kihyun to finally agree to go out with him, a level of persistence uncommon for someone who had been pretty hit-it-and-quit-it until Kihyun had turned his life upside down. 

Well worth it, though. Even if Kihyun is currently ignoring him for dusty bones. 

Mingyu leans back, and nuzzles Kihyun’s thigh. It’s fairly muscular now, which is mainly Mingyu’s doing. He might be putty in Kihyun’s hands in general, but he’s one hell of a motivating personal trainer. Even when he wants his client to fuck him. 

Mingyu’s friends call Kihyun _Mingyu’s DILF,_ and nothing Mingyu does will persuade them to refer to him otherwise. Twenty-eight and thirty-five isn’t even a ten year age gap. _Quite._

“But I’m _bored,”_ he complains, again. Kihyun’s hand tightens more, _painful-sweet-aching._ No other acknowledgement. Mingyu moans, loud and showy, arching up to sell it. _“Yeah,_ hyung, just like that.”

“Shush.” Kihyun keeps watching his show. There’s a scientist-person on screen holding bones up to the camera like a vlogger would a sponsored beauty product. Except with gloves on, and brandishing tiny bone-scraper tools. Or maybe those are to get the dust off? 

Craning his neck, Mingyu watches as Kihyun makes a note on his phone with a thoughtful hum and a small crease in his brow. Mingyu _does not_ _get it._

It’s hot, though, seeing Kihyun in professor-mode. He’s still in his work clothes, tweed jacket draped carefully over the back of the couch and waistcoat buttoned up perfectly. And yes, Mingyu is now conditioned to find _tweed_ sexy.

“How long does it have left, hyung?...” Mingyu whines, Kihyun’s dismissiveness only making him needier. It’s 8:45PM, and Mingyu has to be up at 5AM for an opening shift and the soul-cycle class he’s covering for Seokmin who is _*cough*_ ‘sick’ and totally not _*cough*_ running away for a long weekend with his boyfriend. 

Mingyu would really love to choke on a dick before passing out in Kihyun’s comfortable bed, but if it doesn’t happen soon he’s going to have to be a ‘responsible adult’ and ‘go to sleep early’. Total bummer.

_When did he get so boringly self-aware? Kihyun even makes him floss his teeth before bed each night. He’s practically decrepit._

“Half an hour,” Kihyun replies. Mingyu whines again, and kisses Kihyun’s inner thigh through the perfectly-pressed fabric of his work trousers. Loudly, Kihyun sighs. “What’s got you so worked up, darling?” he asks, finally acknowledging Mingyu’s mood out loud. Kihyun must be feeling charitable tonight. It usually takes far longer for him to do even that. 

“Dunno,” Mingyu says, eloquent. “Work’s getting to me, I guess? I’m having to run everything while Youngji-noona’s on maternity leave. It’s a lot.”

Kihyun doesn’t say: _but it’s just a gym, how hard can it be,_ or: _my job is far more complex._ Mingyu loves him for it. His boyfriend has never looked down on him for their stark difference in careers. They both like their jobs, and that’s good enough for them. 

Mutual respect goes a long way in a relationship. And, whatever they may bring to the bedroom, Kihyun _does_ still respect Mingyu at the end of the day. Insofar that Mingyu had needed to stop Kihyun throwing his expensive red wine in an uppity Philosophy professor’s face at the last faculty party for failing to do so. To be fair, she’d looked down her bespectacled nose at Mingyu (he’d been sitting down, she wasn’t 6’5) and called him _oafish._

Instead of scorn, therefore, Kihyun pauses his documentary. On-screen, the frozen subtitle for his dusty bones documentary reads _‘This specimen has been proven to-’,_ stopping mid-sentence. 

A cliff-hanger. Kihyun hates those. He ignores it for Mingyu, whose needy heart swells in his chest. Turning round entirely, Mingyu tilts his face up. “Kiss?”

Kihyun leans down, and presses a soft kiss to Mingyu’s pouty lips. Pulls back, then. “Do you want to talk about it, sweetheart?”

Decisively, Mingyu shakes his head. “Tired of thinking, hyung,” he replies. It’s obvious— what he’s asking for. He’s close to begging for it, because he really does need to sleep soon. Dancing around such things is an activity for nights where both have the time and energy to do so. 

Kihyun is teaching a class on something ancient and wordy early tomorrow, and he’ll want to be up at 6:30am sharp to iron his shirt and make a kale smoothie. It’s nearly his weekday bedtime, so Mingyu doesn’t want to keep him up long past. His boyfriend’s of an age where sleep deprivation makes him _particularly_ cranky. 

Mingyu adores Kihyun and his unflappable sense of routine. He meal-preps every Sunday night, and sticks recipes on the fridge for the days Mingyu is set to cook (using the silly cartoon dinosaur magnets that Mingyu got him for their first Christmas together— they look incredibly out of place in an otherwise chic kitchen set-up, but Mingyu remembers how prettily Kihyun had smiled when he unwrapped them). 

Mingyu loves Kihyun an absolutely normal amount.

Up tilts Mingyu’s face once more, big hands pawing at Kihyun’s lovely thighs. “Another kiss, hyung?”

Delicate fingers trace the arch of a cheekbone. Mingyu leans into it, openly wanting. “My baby is so needy tonight, hm?” Kihyun remarks. His tone is fond now, rather than continued dismissal. He’s tapped into what Mingyu needs, easy as anything. 

Mingyu’s breath catches, and Kihyun’s eyes linger on the trembling stutter of his lips. _“Yes,_ hyung.”

It’s embarrassing, almost: how easy Mingyu is to read. Overall, however, it benefits them both. Mingyu can be shy with words, and Kihyun is perceptive. _Another kiss. Less chaste, this time— a hint of teeth, sharp and fleeting on his lower lip._ “What will make it better, puppy?”

“I want to sleep here tonight,” Mingyu says, first. There’s nothing uncommon in that after dating for so long, but the subtext reads: _I want to be held._ It’s a longer journey to the gym from here, if only ten minutes or so. Mingyu wants to sacrifice those extra few minutes of sleep for a night in his lover’s embrace. “That alright?”

“Of course,” Kihyun agrees at once, without a second of contemplation. He wets his lips. A flash of pretty teeth. Mingyu’s collarbones feel a dull, phantom ache at the sight. Something like yearning courses through him. “And _before_ you sleep, darling— is there anything you’d like?”

_I’ll make it better,_ Kihyun promises, meaningful glances woven through soft words, _if you want me to._ Whether that be the warmth of his arms or something else entirely. 

Still nosed between spread thighs, knelt as if in reverence, Mingyu yearns to truly worship. “There’s plenty I’d like, hyung,” Mingyu replies. Another kiss to the fabric, higher than before. Kihyun sucks air between his teeth with a soft _hiss—_ he’s sensitive there. “Will hyung let me?”

“Words, darling,” Kihyun reminds, as Mingyu had known he would. It’s part of their dance. With time constraints, though, Kihyun cuts to the chase. “Tell hyung what you want, puppy— it’s nearly our bedtime, after all.”

Before him, Mingyu squirms. Face hot, he admits it, as Kihyun _always_ makes him admit it. Out loud, or nothing. That’s how it goes. “Use my mouth, hyung?” he asks, soft and polite and well-imbued with whininess. “Please?”

“Do I need to get myself out of these,” Kihyun hums an acknowledgement, “or can you manage?”

Mingyu scrambles to be good with earnest, clumsy fingers, and Kihyun’s zipper gets stuck half-way down from his eagerness. Kihyun bats his hand away with a fond sigh, pulling it the rest of the way before leaning back to let Mingyu finish the task. Mingyu’s hand dips past silk to heated skin. Pulls out his cock, flushed and beginning to swell. 

“Thank you, hyung.” For the help, or for Kihyun’s cock itself, Mingyu does not specify. 

“You’re so cute, ‘Gyu,” Kihyun coos, petting Mingyu’s hair as his large hand strokes Kihyun’s cock. Arousal makes Kihyun candid, and Mingyu loves to bask in it. “So _pretty_ on your knees, puppy.”

Mingyu leans against Kihyun’s thigh in an unsuccessful attempt to hide his blush. Whines, _“Hyung…”_ and flushes all the more. 

“Shirt off,” Kihyun snaps his fingers, shrouding his own desire in feigned impatience. He _loves_ how built Mingyu is, but will rarely admit to it out loud. Still, the weight of his gaze is searing as Mingyu pulls his tank top over his head, abs on full display and flexing to show off just a little (just a lot) for his lover. 

“Is this enough, hyung?” Mingyu asks, half-hoping for the chance to undress in full. Doubting he’ll be allowed it so soon.

Kihyun looks him over appraisingly, and considers the question. “For now,” he decides. Mingyu bites back the plea that almost tears past his lips. He _wants_ to wait. They both know that much about him by now. 

Though partially stripping provides some relief, Mingyu feels stifled in his straining sweatpants— he’d be dying right now if he wore pretty trousers like Kihyun, so form-fittingly tight. Kihyun’s still fully clothed, only his cock pulled out for Mingyu to play with. A vision, and a telling indicator of Mingyu’s desperation, of Kihyun’s _indulgence._

It sets Mingyu alight to some indescribable degree. Pathetic, really. He’s gagging for something he’s done countless times before, still just as desperate for it. “Hyung,” he asks, he _whines,_ “how do I always want you this much?”

“I don’t know, darling,” Kihyun admits, still petting, still fond. The calm before a perfect storm that Mingyu aches to be caught in. “You’re adorable, though. Hyung wants his baby too, don’t worry.”

Letting his mouth hang optimistically open, Mingyu whines as Kihyun takes his cock in hand, smearing precum over Mingyu’s lolling tongue. He licks it up, then looks up at Kihyun wide-eyed. “Please?” he asks, oh-so-polite. If Mingyu is _good,_ Kihyun is helpless to his whims, and Mingyu knows it. 

Gentle, at first, Kihyun guides his cock past Mingyu’s willing lips. Lets Mingyu, for a moment, enjoy the fullness and lose himself in it. Then, contemplative, he pulls himself free, clearly wanting Mingyu capable of speech. “Do you want my _full_ focus, pet?” he hums, sensing something in Mingyu’s disposition, “Or would it make my baby feel better to work for my attention?”

It’s a question borne from experience. Kihyun knows Mingyu inside and out, both emotionally _and_ physically, and thus knows every shameful corner of his proclivities. Sometimes, Mingyu likes to be ignored— this varies in severity, from what Kihyun is offering up at present, to Mingyu tied up and desperate as Kihyun touches himself out of reach. 

They don’t have time for _that_ tonight, though Mingyu makes a mental note to ask for it on their next long weekend away together. The cabin they visited last time had _such_ a sturdy headboard. 

Now, however, Mingyu considers what’s on offer. Comes to a decision, and hands Kihyun the TV remote to make his choice clear. As Mingyu sinks back down onto Kihyun’s cock, the presenter finishes her sentence. 

_‘- hail from far earlier than our initial estimate. And that’s just one of the many…’_

Mingyu tunes her monotonous voice out, focusing purely upon Kihyun: the soft sounds he stifles when Mingyu’s tongue dips into his slit, the way his thighs tense under Mingyu’s hands, which are large enough to cover them. Mingyu _loves_ their size difference. Kihyun is no physical match for him, sure, but he can still have Mingyu on his knees with a snap of his delicate fingers. 

It’s the loveliest contrast. Mingyu loves how small he can feel in the wake of Kihyun’s all-consuming presence. 

Kihyun is wearing his glasses tonight, ramping up the Sexy Professor visage, and Mingyu is _so_ goddamn weak for it. His boyfriend rarely gives in to Mingyu’s enthusiastic requests for professor-themed role play, but Mingyu always comes pathetically hard whenever he manages to persuade Kihyun to humour such fantasies. 

Gagging a little as he swallows around him, something he _knows_ gets to Kihyun particularly, Mingyu looks up at his lover for a reaction. Instead, tight lipped, at least, Kihyun picks up his phone and types out another note on the documentary. The fucking _dusty bones._

Mingyu claws at Kihyun’s perfect thighs, and thinks about love. At how _beyond_ in love he is, right now and always.

It may seem strange to some, to those unused to their complexity, but Mingyu knows that Kihyun's commitment to faux-indifference is a sign of his devotion. Kihyun _likes_ praising Mingyu, likes telling him how pretty and good he is as he takes Kihyun’s cock down his throat. But he also knows how Mingyu loves to feel inconsequential sometimes, to be nothing more than a purveyor of pleasure.

Tonight is heading somewhere in between.

Though hard in his sweatpants, Mingyu ignores his own base wants, focusing on Kihyun alone. Kihyun, whose hand rests absentmindedly in Mingyu’s hair as he watches his documentary, giving little indication that his boyfriend is swallowing around his cock. Pulling back and swirling his tongue around the head, Mingyu sets about suckling on it like a lollipop. Kihyun graces him with a reaction at last, hand tightening in Mingyu’s hair as he gasps, eyes still determinedly fixed upon the television.

Pulling Kihyun closer to the edge of the couch, Mingyu urges those perfect thighs over his shoulders, Kihyun flexing almost enough to choke Mingyu between them. _Just how he likes it._ Mingyu takes Kihyun’s dick down again and _holds_ it, as long as he can, swallowing just so that Kihyun’s hips will twitch, fucking his cock just that slightest bit deeper. 

Carefully, Kihyun takes off his glasses and sets them aside. 

Then, at _last,_ one of Mingyu’s large hands cupping his balls as his cock twitches in his boyfriend’s willing mouth, Kihyun discards the façade, too impatient to pretend he isn’t loving it. He holds Mingyu’s hair tight and pulls him off his cock, tipping them both messily backwards as Mingyu takes the cue and surges up to kiss him. 

Together, Kihyun’s trousers kicked off and Mingyu between his thighs, they make out until neither can breathe from it, pulling back to pant into shared air, foreheads leant against one another. Kihyun’s ass, having landed atop the remote, accidentally switches from his pre-recorded documentary to some abstract throwback music channel. _Ke$ha’s_ Tik Tok begins to blast through Kihyun’s expensive speakers, and he wrinkles his nose even as Mingyu shakes above him with laughter. 

“Your ass has good taste, hyung,” Mingyu remarks, breathless. He realises the unintentional innuendo only when Kihyun smirks up at him, still grinding lazily against Mingyu’s clothed thigh.

“You’d know, wouldn’t you?” Kihyun replies, and though the joke is objectively _terrible,_ Mingyu is at once assaulted by perfect memories of _just that._ Kihyun’s legs locked around him, trembling, Mingyu’s tongue spearing deep inside him. The way he likes to trace the marks that Mingyu’s hands grip into his ass afterwards, admiring them in the mirror and feigning disdain as he preens. 

Mingyu kisses him. _“Hyung.”_

“What?” Kihyun teases, hand slipping between them to cup Mingyu’s cock. Pulling down the zipper brings _some_ relief, but Mingyu still feels stifled. “Puppy tired of hyung being mean already? _Aww...”_ Kihyun pouts, _mocking,_ deliciously so.

_“Puppy’s_ gonna blow his load in half a second if you keep talking to me like that, hyung,” Mingyu bites back, rolling his eyes. Tonight’s nothing particularly structured, so he knows he can get away with doing so. _“Please,_ hyung, just wanna come.”

“So cute…” Kihyun murmurs, almost too soft to be audible. Mingyu isn’t sure the praise was even _deliberate,_ and that lapse makes it all the sweeter. 

_Tik Tok_ fades into _Party in the USA,_ and that’s enough to make Kihyun sit up and actively turn off the TV. The sudden silence stretches between them, tangible, until Mingyu spoils it (Mingyu is very good at breaking silence) by clambering into Kihyun’s lap and kissing him. 

_Above_ Kihyun’s lap, really — kneeling either side of Kihyun’s slim thighs, because Kihyun abhors feeling crushed by his muscle-dense lump of an overeager boyfriend. Mingyu knows the word _abhor_ because of just such an instance.

And as he often has to when Mingyu teeters on the threshold of _too_ needy with his kissing technique _(sloppy as fuck,_ one ex called it), Kihyun tangles his fingers in Mingyu’s hair and holds him still, setting the pace. With his free hand, he trails deft fingers down Mingyu’s abs, tracing them with practiced reverence— though Kihyun never admits to worship. Then lower, _lower,_ Kihyun’s hand pops the button on Mingyu’s jeans, taking his cock in hand.

Mingyu moans into the kiss like he’s never been touched before. Some exes found that annoying, or thought he was playing it up to stoke their egos. Kihyun knows he isn’t — knows Mingyu doesn’t _need_ to stoke the ego of someone so effortlessly good in bed — and revels in his neediness instead. 

In the way Mingyu’s hips stutter all desperate and messy. Whining, trembling, chanting _please, please, please,_ until the repetition becomes an unintelligible jumble of sound. 

In the way Mingyu could spill within seconds, fractions of seconds, if Kihyun combined the soft touches with the right dirty words whispered into his ear. 

It’s been a long day. For both of them. Mingyu needs to sleep before another one tomorrow, and his boyfriend knows just how to push him over. 

Kihyun’s teeth are sharp and perfect at the arch of his neck. Mingyu never gets to mark _Kihyun_ so high, but a job outside the stifling codes of academia has its perks. If Jane from two blocks over gives him the stink-eye for showing up to soul-cycle with a hickey, Mingyu won’t lose sleep nor employment over it. 

And Mingyu knows Kihyun’s hand must be covered in precum without looking down, but it’s still that slightest bit shameful as Kihyun slicks it over his cock. When he groans, _“So wet, puppy,”_ against Mingyu’s jawline, moaning as Mingyu paws at him messily, absent of any real rhythm. When he murmurs, _“C’mon, darling, let go,”_ against Mingyu’s greedy lips. 

It’s less kissing, more Mingyu panting and moaning into Kihyun’s mouth, but Kihyun allows it. Enjoys it, even— he doesn’t quite _show_ it, but Mingyu knows. That just about anything Mingyu does when this close is endearing to Kihyun, and how it’s _never been like this before,_ where everything becomes beautiful. Mingyu is loved, and loves, and isn’t afraid to show it.

_At the club, Mingyu’s friends always wishes he were afraid to show it, just a little, because a few drinks in and he’s showing a_ _lot_ _— and damn, that uppity Professor boyfriend of his is down for way more public stuff than expected, huh?_

Mingyu curls into his lover as he comes, and Kihyun _lets_ him despite the dead weight such indulgence invites. Kihyun catches the cum in his palm, and there’s something so _horribly_ attractive to Mingyu at watching Kihyun dirty the handkerchief he pulls from his breast pocket with it. 

So Mingyu has a Stuck Up Professor kink. _Sue him._ Anyone would, dating a man like Kihyun.

Beautiful, perfect Kihyun, who is still hard against Mingyu’s thigh. They rarely come together unless Mingyu is being deliberately denied — which, while fun, is a time consuming affair that they don’t have time for on weekdays. 

Maybe after Kihyun’s Friday class, Mingyu can already be waiting. _There’s_ a thought, though one that can’t get out of hand at present lest Mingyu neglect the moment. _Lest._ Wow, Kihyun really _is_ rubbing off on him. 

Out of sync, therefore Kihyun is still waiting, still _wanting—_ and Mingyu wants to _pass out,_ but his need to see Kihyun come wins over his exhaustion. So he pries himself from Kihyun’s accommodating embrace, knees hitting carpet, and says, “We need to shower _anyway,_ hyung. You might as well, right?”

Then Mingyu looks up at him, lets his tongue loll out _just_ the way Kihyun likes it, and waits.

It’s a win-win; Mingyu is too sleepy to put any real effort into finishing his boyfriend off, and Kihyun _loves_ coming on Mingyu’s face. Mingyu only gets to come on _his_ if he’s really, _really_ earned it, but he doesn’t mind the disparity. Especially if it means a new picture of him all messy carefully locked away on Kihyun’s phone, a little slice of recklessness from his Perfect Professor that makes Mingyu feel a little unhinged if he thinks about it too extensively. 

_This does, too._

Watching Kihyun jack off to the sight of Mingyu knelt before him. The quick, agile flicks of his wrist that show he wants to finish _fast,_ desperate to gaze upon the end result. And the moment _just_ before, where Kihyun’s nose scrunches up in a tell that has Mingyu quickly closing his eyes right as the first streaks of cum paint his face. 

Kihyun’s covering as much ground as he can for the _artistry of it all,_ no doubt, and Mingyu’s drooling a little (a lot) from having his mouth open for so long, and it’s _perfect._ Mingyu loves this part.

“Hold it, darling,” Kihyun coos, voice a little shaky, a little hoarse. _Fucked out._ Mingyu kneels there, cum-coated and drooling, and basks in the attention as Kihyun takes him in. He _hears_ every single picture, because Kihyun refuses to put his phone sounds on mute — only Do Not Disturb while in class. It’s usually eye-roll and grandpa-jibe worthy, but becomes pretty hot in moments like these.

_Phone down, then, and wet-wipes on Mingyu’s skin._

Mingyu closes his mouth and swallows all that landed there like he’s greedy for it. Kihyun swears — like Mingyu doesn’t do it every single time. Routine, but the loveliest kind.

Kihyun helps him up from the floor, his knees a little stiff, and smiles at the way Mingyu sways on his feet. Standing after a while sitting with Kihyun — or knelt on the floor in _front_ of Kihyun — is always a little disorientating. Not that he ever voices it (not _often,_ at least) but Kihyun always seems so small with Mingyu looming above. 

Mingyu adores him. Unwavering and absolute. 

Latching himself to Kihyun’s side — not _hunching,_ because Kihyun scolds him if he risks his back to reduce their height difference — Mingyu hums in contentment. “Hyung?”

Kihyun’s eyes crinkle at the sides as he looks up at him, smile tugging at his lips, radiant. His nerdy little glasses are back on, and Mingyu’s heart thumps like he’s crushing on his boyfriend all over again, watching a History Professor who doesn’t understand exercise machines trying to use an elliptical. _Precious._ “Mhm?”

And Mingyu can’t quite voice the gravity of _all_ he’s feeling in moments like these, not in words that would do it justice. So instead, big hand dwarfing his boyfriend’s as they walk to Kihyun’s pretentiously decorated bathroom, Mingyu just smiles. Carefree, unrestrained, _real._ Then, throwaway in its normality and yet _everything_ all at once, “I love you.”

**Author's Note:**

> i hope you enjoyed this!! pls leave comments/kudos if so, they make me rlly happy and fuel the validation etc <33
> 
> [twt](https://twitter.com/scbaes)  
> [cc](https://curiouscat.qa/scbaes)


End file.
